This invention relates to a control device for a vehicle and a control method for a vehicle.
Japanese Patent Application Laid-Open No. 61-45163 (1986) describes a control device for a vehicle using a gear type transmission. This control device is constructed to achieve smooth speed changing by including a friction clutch on a gear providing the minimum change-speed ratio to the gear type transmission, controlling the number of revolution of the input shaft of the transmission by sliding said friction clutch during the change-speed to synchronize it with the number of revolution of the output shaft of the transmission, and correcting torque reduction occurring during the change-speed with the torque transmitted by said friction clutch.
However, in the prior art control device there is a problem that if during the change-speed the control of the number of revolution only by using the friction clutch, a occupant would receive a sense of incompatibility due to fluctuation of the torque of the output shaft corrected by the friction clutch.
Also, there is a problem that, of the end of the speed, if the torque reduction correcting value during the change-speed corrected by the friction clutch does not match to the torque of the input shaft which is transmitted to the output shaft by a claw clutch, a torque step is caused at the time of the change-speed whereby shaft vibration is generated after the change-speed.
An object of this invention is to improve transmission ability for a vehicle by suppressing the fluctuation of the torque of the output shaft caused from the control of the number of revolution during the change-speed and by reducing a torque step at the end of the change-speed.
This invention relates to a control device for a vehicle having torque transmitting means between the input shaft of a gear type transmission and the output shaft thereof. The torque transmitting means of at least one speed changing stage is comprised by a friction clutch, while the torque transmitting means of the other speed changing stages are comprised by a mesh type clutch. The friction clutch is controlled when the change-speed is effected from the one speed changing stage to the other changing stage. The control device according to the invention comprises torque reduction correcting means, operative, at the time of said change-speed, for correcting the torque reducing part of said output shaft occurring during the change-speed, and revolution number controlling means for controlling the revolution number of said input shaft on the basis of the torque reduction correcting value corrected by said torque reduction correcting means.
Further, the control device according to this invention is characterized in that it further comprises torque adjusting means for adjusting the torque of said input shaft at the end of the change-speed on the basis of said torque reduction correcting value.
Also, this invention relates to a control method for a vehicle wherein torque transmitting means is attached between the input shaft of a gear type transmission and the output shaft thereof. The torque transmitting means of at least one speed changing stage is comprised by a friction clutch, while the torque transmitting means of the other speed changing stages are comprised by a mesh type clutch. The friction clutch is controlled when the change-speed is effected from the one speed changing stage to the other changing stage.
The control method according to the invention comprises the steps of correcting, at the time of said change-speed, the torque reducing part of said output shaft occurring during the change-speed, and controlling the revolution number of said input shaft on the basis of the torque reduction correcting value corrected by said torque reduction correcting mean.
Further, the control method according to this invention is characterized in that it further comprises the step of adjusting the torque of said input shaft at the end of the change-speed on the basis of said torque reduction correcting value.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.